Pressure sintering bonding using a metal-nanoparticle paste or a metal-microparticle paste has been frequently employed as a bonding method for a high-temperature operating semiconductor element. When a semiconductor element and an electrode of a base plate are bonded by thermal press bonding using a metal-nanoparticle paste or a metal-microparticle paste, a cushioning is ordinarily used for the purpose of protecting the surfaces of electrodes of the semiconductor element.
Conventionally, there is disclosed a semiconductor device in which, in order to prevent, when the semiconductor chip is fixed to the base plate with a conductive bond, the wirings from shorting due to a stuck-out portion of the conductive bond, part of the wiring pattern is cut into a groove to thereby trap the stuck-out conductive bond (see Patent Document 1, for example).
There is also disclosed a resin sealed semiconductor device in which the periphery of a semiconductor pellet mounting part is formed to have a protrusion to thereby keep the wires from drooping between the pellet and the lead frame, so that shorting between the pellet and the wirings can be prevented (see Patent Document 2, for example).
There is further disclosed a semiconductor device in which depressions are formed in parts of the conductor pattern on the insulating base plate to mount semiconductor elements and the ticking-out portion of a sinterable metal bond, which is used to bond the semiconductor elements to the conductor pattern, is sandwiched and pressed between a cushioning and the side faces of the depressions, so that the ticking-out portion of the metal bond can be prevented from dropped off (see Patent Document 3, for example).